1. Field of the Invention
The present invention relates to a mechanism for driving an embossing apparatus in an automatic embossing system.
2. Description of the Prior Art
There exist a number of embossing systems for automatic, high-speed embossing of credit cards. One such system is disclosed in U.S. Pat. No. 4,088,216 to LaManna, et al., assigned to the assignee of the present invention.
The system of U.S. Pat. No. 4,088,216 employs a pair of embossing wheels fixedly mounted on a common shaft for rotation, and carrying about their respective peripheries punch and die pairs for all characters available for embossing. The embossing wheels are selectively rotated to position a desired embossing character punch and die pair at an embossing station. The actuating mechanism for the punch and die pair includes a pair of pivotally mounted bail arms continuously driven in an oscillating manner by a complex linkage driven by an eccentric. Each revolution of the eccentric defines an embossing cycle. The bail arms do not directly engage the punch and die pairs but, even when pivoted to a forward position, remain displaced from the engaging ends of the associated punch and die. This permits free rotation of the embossing wheels while the bail arms, as well, are continuously oscillating in the manner indicated above. When the embossing wheels have been rotated to position the punch and die pair of a desired character at the embossing station, at the beginning of the next embossing cycle, interposers are disposed intermediate the ends of the engaging surfaces of the bail arms and the associated engaging ends of the punch and die, thereby to transmit the embossing force from the bail arms to the respective punch and die, causing them to engage and thereby emboss the card.
While the above system operates satisfactorily, the complexity of the linkage mechanism results in a greater chance of breakdown and increases the problem of adjusting the linkage to obtain the proper embossing drive motion. Further, where the element to be embossed has higher structural density or integrity than the conventional plastic credit card, such as a metal identification tag or the like, the increased force required for actuating the punch and die pair imposes additional strength requirements on the linkage mechanism.